Aims: Epithelial-mesenchymal transition (EMT) has been known to play a significant role in tumour progression. Integrin-linked kinase (ILK) has been recently added to the growing list of EMT regulators that control some aspect of carcinogenesis. The aim was to study ILK expression and its relevance to EMT markers in human basal cell carcinoma (BCC).
Methods and results: Paraffin-embedded tissue sections from 100 human BCC cases were processed by immunohistochemistry for the expression of ILK, E-cadherin, Snail, beta-catenin and alpha-smooth muscle actin (alpha-SMA). ILK overexpression was observed in 100% of cases and strongly correlated with tumour invasion and infiltrative BCC. Loss of membranous E-cadherin was found in 71% of cases while nuclear immunoreactivity for E-cadherin was also observed in 90% of the tumours. Snail, nuclear beta-catenin and alpha-SMA expression was detected in 100%, 99% and 97% of tumours, respectively. Aberrant expression of E-cadherin, nuclear beta-catenin and alpha-SMA correlated with BCC tumour invasion. Interestingly, there was a significant correlation between ILK expression and all the EMT markers examined.
Conclusions: ILK overexpression in BCC is implicated in tumour progression probably through the induction of an EMT-related molecular profile. Nuclear localization of E-cadherin in BCC is also associated with aggressive tumour features.